Method of utilizing a fuel gas in refining a petroleum fraction



Patented May 4, 1948 METHOD OF UTILIZING A FUEL GAS IN REFINING A PETROLEUM FRACTION Minor C. K. Jones, Mountainside, N. 1., assignmto Standard Oil Development Company, a corporation of Delaware No Drawing. Application June 15, 1946, Serial No. 677,081

This invention relates to utilization of fuel gas, such ascoke oven gas, water gas, or producer gas,

in catalytic refining of petroleum products.

In many localities the manufacture of hydrogen has been too costly for economical use in refining petroleum products, especially where no suitable resources of natural gas are at hand.

An object of this invention is to provide a method of inexpensively utilizing available city gas or manufactured fuel gas, such as coke oven gas or water gas, containing low purity hydrogen for catalytic refining of petroleum products.

.A further object is to provide a method of enriching manufactured gas, by which it is enhanced in heating value while a portion of its hydrogen content is utilized in satisfactorily refining a petroleum product.

3 Claims. (Cl. 196-24) Catalysts resistant to sulfur poisoning, such as oxides and sulfides of molybdenum and chromium, have been employed commercially in high pressure hydrogenations of low-grade petroleum fractions with requirements of fairly pure hydrogen at high pressures and in large quantities. On the other hand, the metals, such as platinum and nickel, recognized as belonging to the class ofmost active hydrogenation catalysts, very active at low temperatures but, in general, very sensitive to poisonous effects of sulfur compounds present in petroleum products, have not been employed commercially in refining.

In accordance with the present invention, the catalytic material employed in refining petroleum products with manufactured gas under mild conditions of pressure and temperature is very resistant to poisonous action of sulfur compounds, organic peroxides and unsaturated polymers present in petroleum products. These catalytic materials have been used in refining operations continued over 100 hours without loss of activity. They can be regenerated satisfactorily by controlled burning of carbonaceous deposits which tend to form at elevated temperatures. They function to selectively reduce the sulfur content and selectively reduce unstable diolefins in low-grade petroleum fractions. Advantageously, they function to yield an enriched fuel gas product.

To prepare the required catalytic materials for the present purposes, a small amountof a metal or metals selected from the group consisting of platinum and palladium, e. 3., 0.1 to y weight, is incorporated with a carrier of the nature of alumina, which is a hydrous oxide having ultramicroscopic pores. Silica gel is another common example of this kind ofcarrier.

Two types of procedures used for depositing the finely-divided or colloidal metals on the carriers are: (1) impregnation of the carrier with salt solution (e. g., ammonium chloroplatinate or chloroplatinous acid), followed by slow drying, and heat decomposition of the deposited salt; and (2) mulling of the carrier in powdered form with particles of the metal (e. g., platinum black), followed by extruding or pilling. The mulled mixture is extruded wet, then dried. The pilled mixture is dry when compressed into compact form of pill or pellet. The compact form is preferred for the present method.

The pelleted catalytic material may be used in a fixed bed operation or the compact material may be granulated to smaller size for use with a fluid or moving catalyst technique.

Temperatures to be used in upgrading treat ments of low-grade petroleum fractions with a fuel gas and the catalytic material are in the range from about 200 F. to 800 F. but are specifically controlled to obtain selective reduca refinery, locally manufactured city gas (about 30% hydrogen) was used in treating a heavy naphtha product of fluid catalyst cracking for improvement in storage stability over pellets of platinized alumina containing 2% finely-divided platinum. Conditions and results are tabulated as follows:

crating conditions:

p Temperature, F 540 l 2 l l dR to lhr 1% a s cc a v. v. Ga U City Gas Gas Feed Rate, cu. .142 gal".-. 1500 Catalyst Age,hr I 40 Food Product a Gasoline Gasoline magma Octane ratings:

Motor Method. Clear 78.9 Motor Method+3 ml. TEL/gal. 84.4 Research Method Clear 89.8 Research Metl1od+3 ml.

TEL al 95.4

600 $30 200 Peroxide No 23. 7 Trace Trace ASTM Breakdown, Uninhibited 45 830 315 ASTM Breakdown-H 1b. In-

hibitor [5 M gal 75 890 795 Copper Dish Gum, Uninhibited- 621 48 6 Copper Dish Gum-H lb. Inhibitor W M gal 583 36 3 1 n-Butyl aminophenol.

The foregoing data evidence that satisfactory improvement in stability and octane rating was obtained in the treatment. For some unexplained reason, the hydrogenation refining of catalytically cracked gasoline with ordinary city gas was found to give the gasoline better octane ratings than could be obtained by refining with pure hydrogen. Outstanding is the practically complete recovery with selective reduction of diolefins and peroxides.

Further tests show that, in the treatment at 200 F. to 400 F., the peroxides are removed with less effect on the bromine number, and at 600 F. to 800 F. more desulfurization is obtained but with more saturation of the unsaturated hydrocarbon components.

Typical compositions of manufactured fuel gases, such as water gas and coke oven gas, are represented by the following:

TABLE 2 Q Principal fuel gas components Water Gas, Per Cent Coke Oven Fuel Gas Components G, PM can;

In using the fuel gas, hydrogen used up is comthe gas are converted to hydrogen sulfide which can be removed easily, if desired.

The following table shows analyses of manufactored gas before and after use in catalytic hydrogenation of fluid catalyst cracked naphtha. It will be seen that the main change was in the replacement of unsaturates by saturated gaseous hydrocarbons with approximately 10% increase in heat value.

Tests: 3

Catalytic purification and enrichment of menujactured gas over 2% platinum on. alumina in presence of heavy catalytic naphtha Percentage by Volume B. t. u. per

Ci? Gas Product eed Gal carbon Dioxide 5. 2 s. a Eth l 16. 4 0. 2 Propylene--. 2336 0. 5 Butylene 3084 0.0 Oxygen 0.6 0. 4 Carbon Monoxide 322 34. 8 35. 0 Methane 1013 7. l 0. 0 1792 6. 7 7. 0 2590 1. 9 3.4 3370 0. 8 l. 2 1 4016 0. 8 0. 8 Hydrogen. 325 20. 8 25. 0 Nitrogenll. 0 il. 1

Total 100. 0 100. 0

B t u./cu. n 543 501 1 Gas volumes at 60 F. and Hg d Data from Fuel-Flue Gases," American Gas Association, 1940, able No. 30, page 51.

When the catalyst is used at temperatures approaching and above 7 00 F., it tends to become more rapidly coked and thereupon lose activity. However, the coked catalytic material was satisfactorily regenerated by controlled burning of the coke deposit with an air-inert (nitrogen) mixture at temperatures ranging from 700 F, to 1100 F. The regenerated catalytic material was restored to original activity which is an im- .portant factor in commercial use of the precious metal catalysts.

The examples given are for the purpose of illustration and it will be understood that modifications come within the scope of the invention claimed. This invention makes economically feasible hydrogenation treatments of various organic materials and hydrocarbon stocks with low cost gas with concomitant improvement of the gas.

I claim:

1. The method of utilizing a fuel gas in refining a petroleum fraction, which comprises treating said fraction with a fuel gas containing carbon monoxide and hydrogen at 200 F. to 800 F. in the presence of a catalytic material containing a small amount of a metal from the group consisting of platinum and palladium incorporated in a hydrous oxide carrier having -llltllmicroscopic pores.

'2. In a process of stabilizing and improving the antiknock value of a cracked petroleum naphtha, the steps which comprise passing vapor of the naptha with a fuel gas containing carbon monoxide and hydrogen over platinized alumina containing 0.1 to 10% by weight of finely-divided platinum at 200 F. to 700 F., and reducing diolefin components of the naphtha by reaction with the hydrogen in the fuel gas. a

3. The method of improving a cracked petroleum naphtha containing substantial quantities of peroxides and also containing sulfur which comprises passing said naphtha with a fuel gas containing carbon monoxide, unsaturated hydro- 5 carbons and hydrogen into'contact with a pelleted hydrous oxide -carrier containing 0.1 to 10% by weight of a metal from the class consisting of platinum and palladium at temperatures within Number MINOR C. K. JONES.

REFERENCES 0mm Div. 59.)

UNITED STATES PATENTS Name Date Day Oct. 3, 1911 the range of 200700 F. and thereafter recover- 5 1,547,236 Reyerson July 28, 1925 ing the cracked naphtha in stabilized state and th 2,315,144 Watson Mar. 310, 1943 fuel gas increased in heating value. 2,332,572 Hepp et a1. Oct. 26, 1943 2,376,086 Reid May 15, 1945 OTHER REFERENCES Morgan, "A Textbook of American Gas Practice, 2nd edition, vol. 1, pages 25, 30.-

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